GNU/Linux Debian-based Add PostgreSQL 13 Repository
How to Add PostgreSQL 13 Apt Repository for Debian-Based GNU/Linux Systems.
So the PostgreSQL 13 Apt Repo Setup is Valid also for:
- Kali
 - MX Linux
 - Deepin
 - Parrot
 - antiX
 - SparkyLinux
 - Q4OS
 - Vanilla OS
 - Netrunner
 - Voyager Debian
 - MakuluLinux
 - Elive
 - LMDE
 - Devuan
 
Setting up Postgres 13 Debian Apt Repository